Is this one ok? I am sorry I don't really understand this model, especially the frequency character.
module opamp(inm, inp, out);
inout inm, inp, out;
electrical inm,inp,out;
parameter real gain = 250k;
parameter real rgm = 2.3k;
parameter real cc = 30 p;
parameter real rin =2Meg;
electrical vin vo;
analog begin
I(inp, inm) <+ V(inp, inm)/rgm;
V(vin) <+ laplace_nd(gain*V(inp, inm),{1.0},{1.0,5.0e-7});
I(vin, vo) <+ V(vin,vo)/rgm;
I(vo) <+ ddt(cc*V(vo));
V(out) <+ V(vo);
end
endmodule
and my problem is which characters should I consider when I model an opamp?